The invention concerns a process for determining the lubricant power of lubricant oils.
The use of lubricant oils, especially lubricant oils called "automatic transmission fluids" (ATF), in a slip-controlled clutch presupposes accurate knowledge of the friction value curve as a function of the sliding speed. If, in the operating range the curve of the friction value, dependent on the sliding speed, does not correspond to a progressive curve, it is thus expected that self-exciting friction oscillations will occur in the vehicle. Thus, there is no longer an orderly working of slip-controlled clutches, for example, in regulated converter lock-up clutches.
As a rule, lubricant oils are evaluated, with regard to their fitness for use in slip-controlled clutches, by costly test bench superstructures with original installation parts. The values obtained, of course, should not be assigned at once to the lubricant power, rather, but not until after a certain service life of the lubricant oils. Further tests at regular intervals are needed, but not reasonably possible in cost and time spent. For the same reasons, a widespread analysis in vehicle and/or components tests is mostly eliminated. But the knowledge of these values is indispensable when a long-term fitness for lubricant oils must be guaranteed.
The invention is based on the problem of providing a process and a device with which the lubricant power of lubricant oils for slip-controlled clutches can be determined at a low cost so that decisive statements about a long-term fitness are possible.